The below list contains web platforms or self-publishing services that often cause confusion on whether the series is allowed or not. It is mostly for referencing rather than a complete list of what is or is not allowed and can be expanded. Specific print and web magazines aren’t mentioned here.
If the work originally published on ‘Not Accepted‘ websites is later picked up by a professional publisher of the same language, that later publication would be what can be added to the database.
Japanese https://comic-walker.com/ https://comic.pixiv.net/ http://seiga.nicovideo.jp/ https://www.comico.jp/ (Official works only, not Challenge) https://sai-zen-sen.jp/ https://piccoma.com/ https://xoy.webtoons.com/ja (Official words only, not League)
Korean https://comic.naver.com/ (Featured works only, not Challenge) http://webtoon.daum.net/ (Official works only, not League) https://www.lezhin.com/ https://page.kakao.com/ https://www.justoon.co.kr/ http://toomics.com/